• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.505-528
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• 2004

We have reproduced the records of lunar occultation recorded in the History of Three Kingdoms(삼국사기), the History of the Koryo Dynasty (고려사), the Annals of the Choson Dynasty (朝鮮王朝實錄), the Daily Records of Royal Secretariat of the Choson Dynasty (승정원일기), and obtained the epochs of their realizations. We analysed these results to understand how the system of hours had been kept and when a day began. During most of the periods encompassed by these annals, the 12 double hours(12진각법) and the system of 100 divisions of the day (백각법) had been used when the lunar and the solar eclipses were calculated by royal astronomers. In these systems, the starting point of a day is midnight. On the other hand, the five watch system of hours (경점법), in which a night is divided into five watches, was also used. In this system, a day begins at the sunrise. We found that the traditional twilight, called dusk and dawn (혼명) and used in the east Asian countries, largely corresponds to the nautical twilight in modern concepts. This fact means that the Korean expressions and words for time system in every day life had originated form the five watch system of hours. We pointed out that the sunrise and sunset were convenient boundary lines to ancient astronomers, as well as to farmers in the agricultural society. Our results can be used to determine the exact epoch of each astronomical record in chronicles.

• Journal of Internet Computing and Services
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• v.12 no.5
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• pp.21-28
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• 2011

Recently medical and entertainment applications using conducting textile are suggested, but the data of conducting threads are not characterized, classified and verified. Only the data sheet published by manufacturing companies is available. Thus we need to verify the performances of the threading threads in communication. And we need a guideline if the existing communication protocols can be used for the conducting threads communication or the new specific communication protocols have to be developed for the communication. This paper classifies the characteristics of conducting threads made by domestic and overseas companies. Based on the criteria we classified conducting threads into three classes: class A, class B and class C. Further we carried out experiments to verify the adaptability of existing simple serial communication protocols such as RS232. Six different conducting threads are used in experiments and the length of each thread was 0.5m, 1m, 2m and 3m. The data transmission rate and error rate are collected and analyzed. RS485 is very prone to error due to static electricity from human and environment. So it may not be appropriate as long-distance communication protocol up to 12km which is possible in theory. RS232 shows stable and error-less data transmission ability even though every conducting thread didn’t show transmission capability over RS232. USB protocol shows high data rate transmission but the distance cannot be exceeded over 2m. Additionally, USB requires stable power supply. But if the power is supplied through conducting thread, its function is not.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.2
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• pp.179-188
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• 2016

Spent fuels from nuclear power plants, as well as high-level radioactive waste from the recycling of spent fuels, should be safely isolated from human environment for an extremely long time. Recently, meaningful studies on the development of deep borehole radioactive waste disposal system in 3-5 km depth have been carried out in USA and some countries in Europe, due to great advance in deep borehole drilling technology. In this paper, domestic deep geoenvironmental characteristics are preliminarily investigated to analyze the applicability of deep borehole disposal technology in Korea. To do this, state-of-the art technologies in USA and some countries in Europe are reviewed, and geological and geothermal data from the deep boreholes for geothermal usage are analyzed. Based on the results on the crystalline rock depth, the geothermal gradient and the spent fuel types generated in Korea, a preliminary deep borehole concept including disposal canister and sealing system, is suggested.

• Journal of Korean Home Economics Education Association
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• v.31 no.1
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• pp.115-136
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• 2019

The purpose of this study is to analyze the contents of 'housing' unit in middle school Technology-Home Economics textbooks according to the 2015 revision curriculum based on the targets of SDGs. All contents of the ten textbooks of five publishers, such as texts, photographs/figures/tables, activity tasks, and supplementary materials were analyzed in terms of SDGs targets. The number of 'housing' contents among 4 small housing units of Technology-Home Economics book 1 & 2 varied from 64 to 97 by publishers. Beside SDGs4.7, which contains inclusive and general ESDGs, 24 targets of 10 SDGs were found to be related to the contents of 'housing' and were grouped into 15 target categories. The number of SDGs target categories related to housing contents of each small unit and total of all units differed by publishers. Each of 4 small 'housing' units from all the five publishers was related to 6~10 target categories. The contents of five book 1's were related to smaller number of target categories than those of five book 2's. They corresponded to 9 and 12 target categories, consecutively. Only SDGs' target11.1 (appropriate and safe housing and basic services) was related to all the four small units of 'housing' contents among all the five publishers. covering 43.8% of the housing contents. In conclusion, the contents of the 'housing' unit were related to broad range of SDGs targets. Further study could relate goals of teaching-learning plan to various global targets of SDGs according to the contents of 'housing' in order to accomplish ESDGs.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.3
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• pp.92-102
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• 2018

The purpose of this study is to investigate if subjective well-being could be improved by visiting urban forests near residential areas. Because visiting an urban forest is not an intense positive experience, this research is focused on frequency of affective experience rather than intensity. The independent variables are number of visits and length of stay. The dependent variables are positive affect, negative affect, and life satisfaction. A polling agency was employed to select 600 respondents by quota sampling, and data was collected by online survey. The results of ANOVA showed that there was no interaction between the number of visits and length of stay. Regardless of the number of visits, the subjective well-being of visitors of urban forests was enhanced: (a) positive affect of respondents who had visited in the past 2 weeks was increased while negative affect was decreased, and (b) life satisfaction for those who had visited at least 1 time per month was enhanced among usual visitors. The stay of length, however, had little effect on the increase or decrease of these three variables. The results of this study support the existing theory that one could reset their genetically determined happiness set point to a higher level by participating in intentional activities such as visiting urban forests that offer ways to achieve long-lasting changes in well-being. This means that it would be a valuable government investment to construct and maintain urban forests for improving citizens' welfare. A few comments were suggested regarding data collection and inclusion of influencing variables to make future subjective well-being studies more reliable.

• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.588-597
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• 2015

This study is to distribute 5-year-old nuri curriculum science education contents in child picture books, and to investigate the categorical difference of science education contents between domestic and foreign picture books and among genres. The subjects were 219 picture books for children from 4 to 7, listed in which is published by Children's Book Study Group in 2012 and 2013. The research tool was from the article of 5-year-old nuri curriculum nature study, to analyze the contents of young children science education in the child picture books. Content analysis categories was set to two upper-categories and seven sub-categories. Research data were calculated in the analysis of the frequency and percentage of each item's category by the method of analysis conformity. In conclusion, first, in the analyzed result of the upper categories of young children science education contents in 219 picture books, the frequency appeared in order of 'Curious to maintain and expand', 'Learn living things and the natural environment', 'To explore the investigation technique', 'To enjoy the investigation technique', 'Utilize simple tools and machines', 'To search objects and materials', 'Learn natural phenomena'. Second, in the compared result between the domestic and foreign picture books and among genres, "scientific inquiry" is appeared more than "fostering an attitude of exploration".

• The Journal of the Korea Contents Association
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• v.14 no.12
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• pp.1010-1020
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• 2014

This study intended to compare and analyze the difference between resilience and academic stress of juveniles depending on having experience in participating in the camp, and furthermore, to analyze how the camping participation degree of juveniles affect resilience and academic stress. To do so, this study selected teenagers as a population among camping ground users located in Chungcheong and Kyunggi region in 2014, sampled out total 300 participants of 150 camping participants and 150 non-participants using purposive sampling method, then selected final 295 subjects for the final analysis. Validity and credibility of questionnaire were verified through factor analysis and reliability analysis. For data processing, the t-test and multiple regression analysis were used using SPSSWIN 18.00 program. Conclusions are as follows. First, the camp participant group of juveniles showed higher resilience than the non-participant group. Secondly, it was identified that among camping participation degree of juveniles, the resilience of positivity decreased when the length of stay was longer. Thirdly, the camp participant group of juveniles showed lower academic stress than the non-participant group, but did not who significant difference statistically. Fourthly, the school record stress and assignment stress decreased when the participation degree, the length of stay, among camping participation degree of juveniles was longer. Fifthly, it was identified that the better the resilience strengthened by participating in the camp, the academic stress decreased.

• Geophysics and Geophysical Exploration
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• v.20 no.1
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• pp.25-32
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• 2017

We present a 3D SH-wave velocity model of the crust and uppermost mantle and seismic radial anisotropy beneath East Asia. The SH-wave velocity structure model was built using Love-wave group-velocity dispersion data from earthquake data recorded at broadband seismic networks of Korea, Japan, and China. Love-wave group-velocity dispersion curves were obtained by using the multiple filtering technique in the period range of 3 to 150 s for 3,369 event-station pairs. The inverted model using these data sets provides a crust and upper mantle SH-wave velocity structure down to 100 km depth. At 10 ~ 40 km depths SH-wave velocity beneath the East Sea is higher than beneath the Japanese island region. We estimated the Moho beneath the East Sea to be between 10 ~ 20 km depth, while Moho beneath the Korean Peninsula at around 35 km based on the depth where high-velocity anomalies are detected. We estimated the lithosphere-asthenosphere boundary beneath the East Sea to be at around 50 km based on the depth where strong low-velocity anomalies are observed. Widespread low-velocity anomalies are found between 50 ~ 100 km depth in the study region. Positive radial anisotropy ($V_{SV}$ > $V _{SH}$) is observed down to 35 km depth, while negative radial anisotropy ($V_{SV}$ > $V _{SH}$) is observed for deeper depth.

• Journal of The Korean Association For Science Education
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• v.30 no.1
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• pp.170-180
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• 2010

Among the various fields of Earth Science, especially in Astronomy, we often deal with the change of space-time in an abstract way. Thus, making use of 'Concept Sketches'-simplified sketches that represent the main features, principles, processes and interrelationships of the learning content by using some concise explanations, signs and terms could help the students efficiently learn the phenomena of Astronomy. This study's aim was to check its effects and analyze the results of the lessons that included concept sketches and a discussion about the field of Earth Science in high school. The control group took traditional lessons, while the experimental group did a small-group discussion that used the concept sketches. After the lesson, some students were chosen to answer a questionnaire and go through an in-depth interview. The result of the data shows that the small-group discussion lesson that used the concept sketches helped both the high-ranking and low-ranking students to build concepts and was able to attract students' attention. Moreover, the students produced long-term memories of the content learned through the class discussion, which allowed them to exchange their own thoughts and opinions with other students. Most of all, drawing pictures, a familiar activity, appealed to the students, so they took part in the class eagerly.

• Journal of vocational education research
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• v.36 no.2
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• pp.68-94
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• 2017

The purpose of this study is to provide basic data for the development of school education and employment policy by analyzing the differences between image of meister high school students anticipated by industrial HR managers and image actually perceived. For this, semantic differential method developed by Osgood (1957) was selected as the study tool. To find out images of meister high school students, validity of 50 adjectives suggested by Osgood and 21 additional adjectives used in previous studies was reviewed by 10 experts. Final 20 adjectives were selected by excluding adjectives that fail to satisfy validity of contents. Proportional sampling in metropolitan and non-metropolitan areas was done to select 350 final survey samples. A total of 600 surveys were distributed and 230 were returned. Return rate was 38.3%. The results of this study are as follows. First, image of meister high school students anticipated by industrial HR managers showed average score of 2.49, which indicates a positive image. In addition, factor analysis was performed to classify adjectives into groups, and they were divided into three factors including external factor, way of thinking factor, and internal (personality) factor. Second, image of meister high school students currently perceived by industrial HR managers showed average score of 3.24, which indicates a positive image. Third, image of meister high school students currently perceived by industrial HR managers was not as positive as image they anticipate.